Drum sander



Aug. 21, 1951 D. F. WAY 2,565,286

DRUM SANDER Filed Aug. 5, 1950 Dean A Way INVENTOR.

Patented Aug. 21, 1951 UNITED STATES PATENT OFFICE 5 Claims.

This invention comprises novel and useful improvements in a drum sander and more specifically pertains to a rotary sanding drum specifically adapted for use by any rotary power supplying device for providing an efficient, economical and precise machine for sanding jobs.

The object of this invention is to provide a cylindrical drum for detachably receiving sheets of surface treating material, such as sandpaper,

or other surface-treating sheets of fabrics, and adapted for attachment to and rotation by any suitable source of rotary power.

A further object of the invention is to provide a sanding drum of a cylindrical shape composed of complementary sections adapted to receive a sheet of sandpaper or the like upon the cylindrical exterior surface of the sections and retain the ends of the sandpaper in releasable and locked engagement between the adjacent surfaces of the complementary sections.

, A still further object of the invention is to provide an improved sanding drum, as set forth in the foregoing objects, wherein the complementary sections of the cylindrical drum are releasably retained and secured to a driving arbor in an improved manner; wherein the sections are yieldingly and resiliently urged into a position for releasing the ends of the sandpaper; and wherein means are provided for easily, de-

pendably and effectively locking the sections to- I gether to firmly grip and retain the ends of the sandpaper.

A still further object of the invention is to provide an improved sanding drum in which none of the parts or mechanism of the same shall extend beyond the ends of the drum or in any way obstruct the ends or the circumferential surface of the drum.

And a final important object of the invention to be specifically enumerated herein is to provide an improved, inexpensive, compactly recessed and disposed locking means for causing the sections of the drum to clamp upon and retain the ends of a sheet of sandpaper disposed about the drum.

These, together with various ancillary features and objects of the invention which will later become apparent as the following description proceeds, are attained by the present invention, a preferred embodiment of which has been illustrated, by way of example only, in the accompanying drawings, wherein:

Figure 1 is a perspective view showing a suitable ernbodimentof sanding drum incorporating therein the principles of this invention, the drum being illustrated as applied to any conventional rotary power source for rotation thereby;

, Figure 2 is a vertical longitudinal sectional view through the improved sanding drum of Figure 1;

Figure 3 is a vertical transverse sectional view taken substantially upon the plane indicated by the broken section line 3--3 of Figure 2, the drum being shown in its locked position for retaining a sheet of sandpaper thereon; and

Figure 4 is a perspective detail view of the drum locking member.

Referring now more specifically to the accompanying drawings, wherein like numerals designate similar parts throughout the various views, it will be seen that the improved sanding drum forming the-subject of this invention is indicated generally by the numeral l0 and is shown mounted upon an axle l2 carried in a bearing M of any suitable machine constituting a source of rotary power for rotating the sanding drum.

t is to be specifically noted that the improved sanding drum disclosed hereinafter may be used with a variety of machines and is not limited in its use to any particular type of driving machine.

Referring next more specifically to Figures 2 and 3, it will be seen that the drum consists of a pair of complementary sections I6 and 18, which are semicylindrical and which, when placed together, constitute a circular cylinder. The semicylindrical sections 16 and I8 are provided with semicylindrical grooves or channels 20 and 22 which embrace and are mounted upon an arbor 24.

The sections l6 and i8 may be of any desired material, wood, metal or a suitable plastic bein found to be satisfactory for the purposesintended, while the arbor 24 preferably comprises a metallic rod or shaft. As will be readily apparent from Figure 3, the sections of the cylindrical drum are divided along a diametr'ical plane extending through the longitudinal axis of the arbor 24 and of the complementary, semicylindricalgrooves or recesses 20 and 22.

The parts are so proportioned that when the complementary sections embrace the arbor 24, the adjacent surfaces of the section will not contact each other throughout their entire area, but a clearance or notch will be provided between these adjacent surfaces. This notch may be obtained in various ways, as by forming each of the sections 16 and 18 as slightly less than a half circle in cross-section; by cutting away the outer portion of the adjacent surfaces on one side of the arbor 24 of each of the sections to thus provide a wedge-shaped notch or the like; or by forming the semicylindrical recesses and 22 of a lesser diameter than that of the arbor 24. In any event, it is essential that a clearance be provided between the sections when the same are assembled upon the arbor so that the sections shall be capable of a rocking motion towards and from each other about the arbor.

In any convenient location, and preferably adjacent the circumference of the sections, there are provided complementary recesses 25 and 28 which constitute a chamber for receiving a compression spring 30 therein. This compression spring normally urges the sections in opposite directions about the arbor 2'4, to thus cause and resiliently maintain a clearance between the sections. This clearance or the previously mentioned notch is adapted to receive the ends of a sandpaper sheet 33 or a sheet of any other suitable material which is embraced upon the sections l6 and :8.

Referring next more particularly to Figure 2, it is seen that the ends of the drum sections are axially recessed, as at 32 and 34, and that the sections are provided with axial extensions or hubs 35 which extend into these recesses but not beyond the outer ends of the sections.

The arbor 24 is provided with a pair of ferrules, a fixed ferrule being indicated at 38, and received within the recess 34, while a removable ferrule 49 is removably secured upon the screwthreaded extremity 42 of the arbor 24 in the recess 32. These ferrules embrace the annular or cylindrical circumferences of the hubs 35 and retain the same upon the arbor 24.

Thus, neither the ferrules, the resilient means or the locking means to be hereinafter described extend beyond the ends or beyond the cylindrical exterior surface of the drum.

Referring now more particularly to Figures 2 and 4, it will be seen that the locking means provided for overriding or overcoming the re sistance of the spring 30 and which thereby locks I the sections [6 and 18 in position to clamp the ends of the sandpaper sheet therebetween consists of a cylinder 44 of any desired material, and which at its opposite ends is provided with eccentric extensions 46 and 48. The extension 46 is in turn provided with a cylindrical head '50 which may be provided with a kerf 52. The extension 48 is pointed, while the extension is cylindrical, both of the extensions constituting journal bearings, as will now be apparent.

The adjacent surfaces of the sections 15 and H3, upon the diametrically opposite side of the cylinder from the arbor 24, are provided with complementary semi-cylindrical recesses or chambers 54 and 56. These chambers in turn have bearing or journal recesses 58 and 58, which respectively receive the journal extensions 48 and 45 of the locking member. The headed portion 50 extends into the recess 32 for easy access by a screwdriver or the like. It will now be apparent that the locking cylinder 44 is eccentrically positioned in the complementary chambers 54 and 56 and that, upon rotation of the locking member, the eccentric cylinder 44 will be rotated about the axis of the journal bearing extensions 43 and 48 to thereby cause opposite oscillations of the sections I6 and 18 about the arbor 24, and thereby, in turn, clamp the sections upon the sheet whose ends are positioned therebetween.

From the foregoing, it is thought that the construction and operation of the device will be readily apparent and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art after a consideration of the foregoing specification and accompanying drawings, it is not desired to limit the invention to the exact construction shown and de scribed, but all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claims.

Having thus disclosed and described the invention, what is claimed as new is as follows:

1. A sanding drum comprising an arbor, a drum including sections mounted on said arbor, said sections having a cylindrical outer surface for receiving thereon a sheet of sandpaper, retaining means for securing said sections upon said arbor, the adjacent edges of adjacent sections defining a notch for receiving the ends of a sandpaper sheet, resilient means urging said adjacent edges apart, locking means for closing adjacent edges together, said locking means being positioned between said sections and on the opposite side of the arbor from the resilient means.

2. A sanding drum comprising an arbor, a drum including sections mounted on said arbor, said sections having a cylindrical outer surface for receiving thereon a sheet of sandpaper, retaining means for securing said sections upon said arbor, the adjacent edges of adjacent sections defining a notch for receiving the ends of a sandpaper sheet, resilient means urging said adjacent edges apart, locking means for closing said adjacent edges together, said locking means including complementary chambers in the adjacent surfaces of said sections, a wedge member in said chambers for moving said sections.

3. A sanding drum comprising an arbor, a drum including sections mounted on said arbor, said sections having a cylindrical outer surface for receiving thereon a sheet of sandpaper, retaining means for securing said sections upon said arbor, the adjacent edges of adjacent sections defining a notch for receiving the ends of a sandpaper sheet, resilient means urging said adjacent edges apart, locking means for closing said adjacent edges together, said locking means including complementary chambers in the adjacent surfaces of said sections, a wedge member in said chambers for moving said sections, said wedge member constituting an eccentric.

4. A sanding drum comprising an arbor, a drum including sections mounted on said arbor, said sections having a cylindrical outer surface for receiving thereon a sheet of sandpaper, retaining means for securing said sections upon said arbor, the adjacent edges of adjacent sections defining a notch for receiving the ends of a sandpaper sheet, resilient means urging said adjacent edges apart, locking means for closing said adjacent edges together, said locking means including complementary chambers in the adjacent surfaces of said sections, a wedge member in said chambers for moving said sections, said wedge member constituting an eccentric composed of a cylinder and an eccentric journal bearing for the same.

5. A sanding drum comprising an arbor, a drum including sections mounted on said arbor, said sections having a cylindrical outer surface for receiving thereon a sheet of sandpaper, retaining means for securing said sections upon said arbor, the adjacent edges of adjacent sections defining a notch for receiving the ends of a sandpaper sheet, resilient means urging said adjacent edges apart, locking means for closing said adjacent edges together, said locking means comprising a cylinder, complementary chambers in adjacent surfaces of adjacent sections receiving said cylinder, eccentric shafts extending axially from opposite ends of said cylinder for journaling the latter in said sections, an actuating head on one of said shafts extending exteriorly of said drum.

DEAN F. WAY.

REFERENCES CITED The following references are of record in the file of this patent:

Number Number 6 UNITED STATES PATENTS Name Date Ross Oct. 25, 1898 Terry Aug. 16, 1921 Chudner May 31, 1949 FOREIGN PATENTS Country Date Great Britain Nov. 2, 1933 Germany Aug. 24, 1926 Germany Nov. 15, 1932 

